Power down button works well, PiDP-10 card configured for a friend

THE POWER DOWN BUTTON CONNECTED TO RPi 5 BOARD WORKS PERFECTLY

I wired up the pushbutton to the J2 pads on the Raspberry Pi 5 and tested it out. Indeed, when you push the button twice, it does a proper shutdown and then powers down the Pi. This is the functionality I needed to have in place to support the friend (see below) who will run this strictly as a PDP-10 console replica but never connect over networks to it. 

SET UP SD CARD FOR A FRIEND WHO BOUGHT A PRE-BUILT PiDP-10

I configured the latest 64 bit Debian Linux for the Raspberry Pi, set it up for the east coast of the US, and installed the PiDP-10 software on it. Testing it on my kit, I ran the replica in the same way as the friend, using the button on the rear to safely power down at the end of my test. 

The friend has received a pre-built PiDP-10 product. He bought a Raspberry Pi 5 to stick inside to power it, but didn't have the monitor, keyboard, or network terminal access to do the configuration himself. I set up an SD card so that he can slip it into the RPi then power up and enjoy his console. 

Comments

Post a Comment

Popular posts from this blog

Bizarre behavior detected in a Raspberry Pi Pico based design and partially understood

ORIENTATION OF THE PRODUCT CAN CAUSE THE PI TO FREEZE AT STARTUP This particular product with a Raspberry Pi Pico would not boot up when sitting flat on the table in its normal orientation, but if tilted or turned it would come right up. When I hooked up a USB serial connection to the debug header, it worked fine even flat on the table.  INVESTIGATION BY DESIGNER AS WELL AS ME I first assumed that I had introduced this problem in the product, but happened to describe it to the maker who was able to reproduce it reliably. I continued to try variations to determine whether it was pressure on a board or component that caused it. I also searched the web for any reports that might cause Pi Picos to fail to boot based on orientation, but found nothing.  The designer found signals introduced on a serial connection trace when sitting in the normal (failing) orientation but not injected when rotated or otherwise turned. Traces were routed from the UART0 on the Pico to a header, for use...
Read more

Incompetent coders - the frustration of using Vivado to build FPGA designs

IDIOT SOFTWARE MUST BE RESTARTED CONSTANTLY TO SEE INPUT FILE CHANGES When I update a source file, often Vivado is somehow working from a cached copy and never notices the changes. It is highly frustrating to fix an issue, rerun a Linter or Synthesis and get the same old errors. The only solution is to shut Vivado down and restart. I remember hitting this many times in past years as I worked with the toolchain, but it has changed from sporadic to nearly constant failure to see the changed timestamp. I can't be the only person running the toolchain under Windows, yet this kind of bumbling misperformance has been a feature for years. 
Read more

Found correct mod for the Arduino Mega 2560 to avoid powering it from USB

Image
USB HANDLING CIRCUITS IN THE MICROPROCESSOR REQUIRE USB VCC TO RUN The reason my first attempt failed, simply removing the poly (resettable) fuse, is that the fuse is between the USB connector and the microchip which needs the USB VCC connected. I had to reinstall the fuse.  BETTER CHANGE IS TO REMOVE A MOSFET THAT ROUTES POWER The Arduino uses a power mosfet and a comparator to decide when the external power is adequate to run the board, disconnecting the USB VCC from the board. It does leave that wire connected to the USB circuitry in the chip, however. With the transistor removed, the USB power never gets to the board so it is always powered by the external (1130) power. This means the board powers up and down with the main system, whether or not a USB cable is connected to anything else. When the board is powered up, the cable is active as a serial connection, exactly what I wanted to happen.  In the picture below, the green circle shows the reinstalled polyfuse. The red c...
Read more